[2] Some varieties of the extinct bull-and-terrier dog from the British Isles began to find their way into America[2] as early as 1850.

This varieties became a breed recognized by the United Kennel Club as American Pit Bull Terrier in 1898.

In 1936 the American Kennel Club accepted to recognized the breed with a different name and registered a some individuals in the stud book.

[7][8][9][10][11] The AKC closed and opened the AmStaff Stud Book to UKC registered American Pit Bull Terrier dogs a few more times until the 1970s.

[12] According to AKC's published breed standard which was approved June 10, 1936, the "American Staffordshire Terrier should give the impression of great strength for his size, a well put-together dog, muscular, but agile and graceful, keenly alive to his surroundings.

His head should be medium in length with a broad skull, a distinct stop, and pronounced muscles in the cheek.

Breed Specific Legislation has been enacted in various countries including the United States,[19] France,[20] Australia,[21] Austria,[22] Canada,[23] Denmark,[24] Germany,[25] Kanpur,[26] Ireland,[27] Norway,[28] and Turkey.